Circadian Rhythm

When we talk about light, it’s only natural to start by talking about how it relates to our biological functions. When we talk about light, it’s only natural to start by talking about how it relates to our biological functions. Every living beings have internal built-in clock that regulates the biological process. This clock is what is known as the circadian rhythm. Circa = around or approximately, diem = dia (day). One cycle of this clock takes approximately 24 hours (a day). It determines when we tend to wake up, when we feel the most energetic during the day, and we feel like falling asleep. Although there is an internal system that regulates all these, of course external factors play important role on how exactly the body would function. One of these factors is light.

When closed, the eye is actually still capable of sensing light. This exposure to light in the morning after waking up triggers the hormonal process that advances the circadian clock. Exposure to light at night before sleeping would on the other hand delay the rhythm. This is why it is important to have our bedroom exposed to natural light. I lived or stayed in hundreds of houses abroad, and every bedrooms and most bathrooms have window or opening to the outside, exposed to natural light. The architecture of a building will work to accommodate this basic yet important need. But this is not the case in Indonesia.

In this modern day, the planning in Indonesia in general is so bad and put more importance on economic than biological aspect. In fact, in the houses I grew up in, my bedrooms almost always didn’t have opening to the outside. Most have windows but facing either the courtyard or the dining room, which is not really accommodating as we usually put curtains for privacy, and say goodbye to natural light. Even in my current apartment, my bedroom doesn’t have any opening at all. At all. Luckily I live alone and can leave the door open all day to be still exposed by natural light. Most middle class buildings are built just to have maximum usage of the land for maximum profit. Maybe because the people here takes for granted being so used to live in an equatorial country exposed to the sun all day all year long so the important of natural light is somehow massively neglected. People would rather have a working aircon than having a proper window. But let me tell you growing up in a bedroom not exposed to the outside was miserable.

These days though, we could purchase an artificial lighting device that could mimic the colour of natural light and set according to the natural time of sunrise. “Simulated sunrise” as they called it. I haven’t tried this personally but I’ve read some great review about how it helps those sleeping in a windowless room. There must be a certain color temperature or wavelength required for it to works with our natural biological process, I will get back into this later.

In general I think people who live in countries with four seasons appreciates light way more than us who live in the equator. But I also often wonder about those who live in extreme condition in the northern hemisphere where they have six months of light and six months of darkness. I found an interesting study we can read here. And I’m not going to write about it further as I don’t have much experience and knowledge on it.

After all, starting with this very basic exposition of the importance of light, and at the same time the very negligence of the people in this country is to it, is basically why I was interested in studying it further at first place. This will change in the future I hope, but in the meantime let us keep educating ourselves hehe.

Note. More details on how the circadian rhythm works can be find on the book Why We Sleep, which I’m currently reading.

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